Rolex Datejust 'Thunderbird' (design 1625) : The Datejust types were introduced with a coin edge bezel, which afterwards were changed by a new fluted bezel alongside with a bigger crown. In the mid-50's, Rolex introduced the Datejust (design 6605) with the cyclops, or the magnifying bubble that is positioned over the date on the watch's crystal. In 1956, Rolex unveiled a Datejust model called the